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1.
Biofouling ; 40(7): 431-445, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38973173

RESUMO

Candida albicans is often implicated in nosocomial infections with fatal consequences. Its virulence is contributed to hydrolytic enzymes and biofilm formation. Previous research focused on studying these virulence factors individually. Therefore, this study aimed to investigate the impact of biofilm formation on the hydrolytic activity using an adapted low-cost method. Eleven strains of C. albicans were used. The biofilms were formed on pre-treated silicone discs using 24-well plates and then deposited on the appropriate agar to test each enzyme, while the planktonic cells were conventionally seeded. Biofilms were analysed using Raman spectroscopy, fluorescent and scanning electron microscopy. The adapted method provided an evaluation of hydrolytic enzymes activity in C. albicans biofilm and showed that sessile cells had a higher phospholipase and proteinase activities compared with planktonic cells. These findings were supported by spectroscopic and microscopic analyses, which provided valuable insights into the virulence mechanisms of C. albicans during biofilm formation.


Assuntos
Biofilmes , Candida albicans , Plâncton , Candida albicans/fisiologia , Biofilmes/crescimento & desenvolvimento , Hidrólise , Microscopia Eletrônica de Varredura , Fosfolipases/metabolismo , Análise Espectral Raman/métodos , Peptídeo Hidrolases/metabolismo
2.
Insect Sci ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014530

RESUMO

The escalating use of nanodiamonds (NDs) has raised concerns about their ecotoxicological impact, prompting exploration of therapeutic interventions. This paper pioneers the examination of Vitamin B12-conjugated sericin (VB12-SER) as a potential therapeutic approach against ND-induced toxicity in darkling beetles (Blaps polychresta). The study analyzes mortality rates and organ-specific effects, covering the testis, ovary, and midgut, before and after treatments. Following exposure to 10 mg NDs/g body weight, within a subgroup of individuals termed ND2 with a mortality rate below 50%, two therapeutic treatments were administered, including pure sericin (SER) at 10 mg/mL and VB12-SER at 10.12 mg/mL. Consequently, five experimental groups (control, SER, ND2, ND2+SER, ND2+SER+VB12) were considered. Kaplan-Meier survival analysis was performed to assess the lifespan distribution of the insects in these groups over a 30-d period. Analyses revealed increased mortality and significant abnormalities induced by NDs within the examined organs, including cell death, DNA damage, enzyme dysregulation, antioxidant imbalances, protein depletion, lipid peroxidation, and morphological deformities. In contrast, the proposed treatments, especially (ND2+SER+VB12), demonstrated remarkable recovery, highlighting VB12-conjugated SER's potential in mitigating ND-triggered adverse effects. Molecular docking simulations affirmed binding stability and favorable interactions of the VB12-SER complex with target proteins. This research enhances understanding of NDs' effects on B. polychresta, proposing it as an effective bioindicator, and introduces VB12-conjugated SER as a promising therapeutic strategy in nanotoxicological studies.

3.
Mar Pollut Bull ; 205: 116650, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38981195

RESUMO

This study examines diatom assemblages in the Matsu Archipelago, an area influenced by Minjiang River runoff. It focuses on harmful algal blooms (HABs) that occurred between August 2021 and July 2022. Utilizing 18S rRNA metabarcoding and microscopic analysis, we observed a significant diatom bloom during early summer runoff, peaking at 5 × 105 cells L-1. The research reveals dynamic community changes during the runoff season, with dominant genera including Pseudo-nitzschia, Chaetoceros, and Skeletonema. Skeletonema cell density correlated with NO3 levels, Chaetoceros had a slight PO4 affinity, and Pseudo-nitzschia showed a negative correlation with Skeletonema. Pseudo-nitzschia, which prefers high light and pH conditions, had notably high concentrations in the flood season and in the autumn. In both, it was dominated by potential toxin-producing species - P. multistriata and P. pungens during the flooding, and P. cuspidate in the autumn. These findings highlight the intricate relationship between diatom dynamics and environmental factors, providing essential insights for managing HABs, especially Pseudo-nitzschia species, amidst environmental changes.


Assuntos
Diatomáceas , Monitoramento Ambiental , Inundações , Proliferação Nociva de Algas , Rios , China , RNA Ribossômico 18S , Estações do Ano
4.
Cureus ; 16(6): e62083, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38989334

RESUMO

Ehlers-Danlos syndrome (EDS) is a collection of genetic disorders caused by abnormalities in collagen and typified by hyperflexible joints, hyperextensible skin, and a tendency for easy bruising and tissue injuries. Hypermobile Ehlers-Danlos syndrome (hEDS), the most common subtype, presents a diagnostic challenge due to the lack of specific genetic markers. This case report describes a 13-year-old girl with hEDS, presenting with hypermobility, thoracolumbar scoliosis, constipation, glucosuria, microscopic hematuria, urticaria, and intermittent episodes of bilateral hand and feet swelling. Genetic testing revealed a variant of uncertain significance in the COL9A2 gene. An echocardiogram showed a mildly dilated aortic root. The complexity of her presentation underscores the challenges in diagnosing and managing hEDS with multisystem involvement.

5.
Sci Rep ; 14(1): 17092, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39048604

RESUMO

To compare unused phacoemulsification tips and those used different times with different techniques of cataract surgery (divide and conquer and chop), in vivo phacoemulsifications were performed with tips of different numbers of operation. These were compared with the same number of sterilized-only and unused tips with the help of an atomic force microscope. Comparison of roughness values (Sa, Sq), geometric and measurable flange length and surface was also performed (profile length %, area %). The differences between the parameters that can be measured during surgery (average ultrasound percentage, US ave %, Average Phaco Time, APT) were also analyzed. We found significant correlations between age and lens hardness (p = 0.0045), area % and APT (p = 0.03), between area % and US ave% (p = 0.03) and also between the two surgical techniques in terms of area% (p = 0.04) and US ave % (p < 0.01). Roughness increased with the number of uses. An increase in profile length% can be observed up to the twentieth operation. This can result from scratches and microscopic damages and also from abrasion and possible material additions on the surface of the needles. The divide and conquer technique causes less microscopic damage to the surface, and smaller average US energy is required during surgery.


Assuntos
Facoemulsificação , Facoemulsificação/métodos , Facoemulsificação/efeitos adversos , Humanos , Idoso , Feminino , Masculino , Pessoa de Meia-Idade , Extração de Catarata/métodos , Catarata/patologia , Idoso de 80 Anos ou mais , Microscopia de Força Atômica
6.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 42(3): 409-414, 2024 Jun 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-39049663

RESUMO

Dental invagination is an abnormality of the crown or root development induced during tooth germ development when the enamel-forming apparatus or epithelial root sheath overpopulates and folds into the papilla. In severe cases, the invaginated channels are connected to the pulp and periodontal tissues, often causing endodontic and periapical diseases. The complex anatomical pattern of this disease adds difficulty in its preoperative diagnosis and clinical operation. In this paper, we report a case of non-surgical treatment assisted by cone beam CT and microscopy for maxillary lateral incisor double dens invaginatus type Ⅲ (Ⅲa and Ⅲb) with apical periapical infection. After 1-year follow-up, the affected tooth was asymptomatic and the periapical lesion was significantly reduced.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Dens in Dente , Incisivo , Periodontite Periapical , Humanos , Incisivo/anormalidades , Maxila
7.
Sci Prog ; 107(3): 368504241261592, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39051495

RESUMO

To clarify the impact of moisture content and dry density on the strength of loess, the remolded loess samples with different moisture content and dry density were prepared, and the influence of moisture content and dry density on loess strength was explored from the macro level by direct shear test without suction control. On this basis, the mechanism of the influence of moisture content and dry density on loess strength was explored from the micro level by nuclear magnetic resonance method. The research results indicate that: In the case of low water content, there are peak points in the stress-strain curve of remolded loess, exhibiting strain softening characteristics. In the case of high water content, there is no obvious peak in the stress-strain curve, exhibiting strain hardening characteristics. Moisture has a significant impact on the shear strength of remolded loess. As the moisture content of the soil sample increases, the cohesion decreases significantly, and the change in internal friction angle is not obvious. As the moisture content continues to increase, the free water content continues to increase. Free water will continuously soften the soil particle structure, reduce the bonding force between soil particles, and cause the cohesion to decrease with the increase of moisture content. The change in dry density also has a significant impact on the shear strength parameters of remolded loess. As the dry density of the soil sample increases, the cohesion increases. The smaller the dry density, the larger the pore ratio, and the looser the contact between soil particles, weakening the bonding effect. The larger the pore ratio, the more bound water is converted to free water, and the strong bonding force between the water film and soil particles disappears. Both of these microscopic factors can lead to a decrease in cohesion with a decrease in dry density.

8.
J Fungi (Basel) ; 10(7)2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39057373

RESUMO

This paper investigated the inhibitory effect of Sesamol (Ses) on Pestalotiopsis neglecta. The potential inhibitory mechanisms were explored by observing changes in cell morphology, measuring alterations in cell membrane-related indices, as well as energy metabolism-related indices and changes in enzyme activities related to virulence. The results show that Ses completely inhibited the growth of P. neglecta at 600 µg/mL (minimum inhibitory concentration and minimum fungicidal concentration), with an EC50 of 142 ± 13.22 µg/mL. As observed with scanning electron microscopy (SEM) and transmission electron microscopy (TEM), Ses treatment resulted in the breakage and crumpling of P. neglecta cell membrane and organelle lysis. Ergosterol content and the total lipid in P. neglecta treated with 300 µg/mL Ses was 91.52% and 54% of that in the control groups, respectively. In addition, spores were stained, increased leakage of intracellular constituents at 260 nm, and decreased extracellular pH. This suggests damage to the cell membrane integrity and permeability. Furthermore, Ses decreased the ATP levels and key enzymes in the tricarboxylic acid (TCA) cycle, indicating interference with the fungal energy metabolism. Moreover, the activities of polygalacturonase (PG) and endoglucanase (EG) of P. neglecta treated with 300 µg/mL of Ses were only 28.20% and 29.13% of that in the control groups, respectively, indicating that Ses can reduce the virulence of P. neglecta. In conclusion, our results show that Ses should be considered as a potential plant-derived fungicide due to its ability to disrupt the morphology of P. neglecta, damage cell membrane integrity and permeability in P. neglecta, interfere with energy metabolism, and reduce its virulence, ultimately affecting the fungal growth.

9.
J Toxicol Pathol ; 37(3): 109-126, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38962260

RESUMO

The historical control database of a multinational laboratory services provider was queried for all histopathologic findings in New Zealand White rabbits which were used as control animals during a ten-year period (2011-2020). The query included all evaluated tissues, with or without microscopic findings, in studies conducted for safety testing for regulatory approval by the U.S. Food and Drug Agency (FDA) or the U.S. Environmental Protection Agency. A second query included studies conducted in the United Kingdom for control rabbits used in studies compliant with the Healthcare Products Regulatory Agency (MHRA) and/or the European Medicines Agency (EMA), which provide regulatory oversight in the United Kingdom and European Union, respectively. Infiltrates of inflammatory (mixed or mononuclear) cells were commonly noted in various organs including heart, digestive tract, muscle, thyroid, kidney, urinary bladder, eyelid, ocular structures, harderian gland, lacrimal gland, and lung. Mineralization was noted in aorta, kidney, urinary bladder, and ovary. Also noted were degeneration/necrosis in the myocardium, and intramuscular injection sites of the skin, degeneration/regeneration of muscle and diaphragm, ectopic tissue in the pancreas and thyroid, basophilic foci in salivary gland, increased/decreased vacuolation in adrenal gland, increased/decreased lymphocytic cellularity of lymph nodes, intrasinusoidal erythrocytes in lymph nodes, thymic atrophy, increased adipocytes in bone marrow, inflammatory cell foci in the liver and gall bladder, lacrimal gland atrophy, renal tubule basophilia, degeneration/regeneration, and dilatation; oviduct cyst; in the testis, degeneration/atrophy, cellular debris, dilatation, decreased sperm and segmental hypoplasia of seminiferous tubules; and squamous metaplasia of the testis and seminal vesicle.

10.
Front Oncol ; 14: 1396887, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38962265

RESUMO

Pathological images are considered the gold standard for clinical diagnosis and cancer grading. Automatic segmentation of pathological images is a fundamental and crucial step in constructing powerful computer-aided diagnostic systems. Medical microscopic hyperspectral pathological images can provide additional spectral information, further distinguishing different chemical components of biological tissues, offering new insights for accurate segmentation of pathological images. However, hyperspectral pathological images have higher resolution and larger area, and their annotation requires more time and clinical experience. The lack of precise annotations limits the progress of research in pathological image segmentation. In this paper, we propose a novel semi-supervised segmentation method for microscopic hyperspectral pathological images based on multi-consistency learning (MCL-Net), which combines consistency regularization methods with pseudo-labeling techniques. The MCL-Net architecture employs a shared encoder and multiple independent decoders. We introduce a Soft-Hard pseudo-label generation strategy in MCL-Net to generate pseudo-labels that are closer to real labels for pathological images. Furthermore, we propose a multi-consistency learning strategy, treating pseudo-labels generated by the Soft-Hard process as real labels, by promoting consistency between predictions of different decoders, enabling the model to learn more sample features. Extensive experiments in this paper demonstrate the effectiveness of the proposed method, providing new insights for the segmentation of microscopic hyperspectral tissue pathology images.

11.
Artigo em Inglês | MEDLINE | ID: mdl-38963730

RESUMO

BACKGROUND: Microscopic colitis (MC) is an inflammatory disorder of the colon. To date, the relationship between inflammatory eye diseases and MC is unclear. OBJECTIVE: To assess whether inflammatory eye disease (iridocyclitis and episcleritis) is a risk factor for MC. METHODS: We conducted a nationwide matched case control study in Sweden leveraging the ESPRESSO-study (a Swedish database containing data on all biopsies from the gastrointestinal tract from 1965 to 2017). In total, we identified 14,338 patients with biopsy-verified MC (diagnosed from 1981 to 2017). Patients with MC were matched (by age, sex, county and year of birth) with 68,753 controls from the general population and the occurrence of preceding inflammatory eye diseases (defined as diagnosis of episcleritis or iridocyclitis) in the two groups was compared. Multivariable adjusted odds ratios (aORs) were calculated using conditional logistic regression conditioned on the matching variables. RESULTS: A majority of patients with MC were women (71.9%) and the median age at MC diagnosis was 63.3 years (interquartile range (IQR) = 50.7-72.6). Some 225 (1.6%) MC patients had an earlier record of inflammatory eye disease compared with 614 (0.9%) in controls. These figures corresponded to an aOR of 1.77 (95% CI = 1.52-2.07) for inflammatory eye diseases in patients with MC. Compared to siblings, the aOR for previous inflammatory eye diseases in MC was 1.52 (95% CI = 1.17-1.98) and patients treated with budesonide, as a proxy for clinically significant disease, had a somewhat higher aOR for previous inflammatory eye diseases. CONCLUSION: Inflammatory eye diseases are more common in patients subsequently being diagnosed with MC. Our findings highlight that these conditions may have shared causes and inflammatory pathways and are of clinical interest to gastroenterologists, ophthalmologists and general practitioners.

12.
Open Life Sci ; 19(1): 20220859, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39005738

RESUMO

This work investigated the high-throughput classification performance of microscopic images of mesenchymal stem cells (MSCs) using a hyperspectral imaging-based separable convolutional neural network (CNN) (H-SCNN) model. Human bone marrow mesenchymal stem cells (hBMSCs) were cultured, and microscopic images were acquired using a fully automated microscope. Flow cytometry (FCT) was employed for functional classification. Subsequently, the H-SCNN model was established. The hyperspectral microscopic (HSM) images were created, and the spatial-spectral combined distance (SSCD) was employed to derive the spatial-spectral neighbors (SSNs) for each pixel in the training set to determine the optimal parameters. Then, a separable CNN (SCNN) was adopted instead of the classic convolutional layer. Additionally, cultured cells were seeded into 96-well plates, and high-functioning hBMSCs were screened using both manual visual inspection (MV group) and the H-SCNN model (H-SCNN group), with each group consisting of 96 samples. FCT served as the benchmark to compare the area under the curve (AUC), F1 score, accuracy (Acc), sensitivity (Sen), specificity (Spe), positive predictive value (PPV), and negative predictive value (NPV) between the manual and model groups. The best classification Acc was 0.862 when using window size of 9 and 12 SSNs. The classification Acc of the SCNN model, ResNet model, and VGGNet model gradually increased with the increase in sample size, reaching 89.56 ± 3.09, 80.61 ± 2.83, and 80.06 ± 3.01%, respectively at the sample size of 100. The corresponding training time for the SCNN model was significantly shorter at 21.32 ± 1.09 min compared to ResNet (36.09 ± 3.11 min) and VGGNet models (34.73 ± 3.72 min) (P < 0.05). Furthermore, the classification AUC, F1 score, Acc, Sen, Spe, PPV, and NPV were all higher in the H-SCNN group, with significantly less time required (P < 0.05). Microscopic images based on the H-SCNN model proved to be effective for the classification assessment of hBMSCs, demonstrating excellent performance in classification Acc and efficiency, enabling its potential to be a powerful tool in future MSCs research.

13.
Artigo em Inglês | MEDLINE | ID: mdl-39001920

RESUMO

PURPOSE: This study aimed to conduct a comparative analysis of audiological and postoperative clinical outcomes between the endoscopic and microscopic stapedotomy approaches. METHODS: This study employed a randomized, controlled design. Twenty-seven patients with bilateral otosclerosis underwent stapedotomy in both ears, with randomized allocation of the surgical technique (endoscopic vs. microscopic) for the first operated ear. Air-bone gap (ABG) and ABG gain were measured at least 12 months postoperatively. Postoperative outcomes including pain (Visual Analog Scale-VAS), dizziness, early-term (day 1) and late-term (6 months) dysgeusia were evaluated. The Glasgow Benefit Inventory (GBI) assessed health-related quality of life at one month postoperatively, and operative time was measured. RESULTS: This study compared endoscopic (n = 27 ears) and microscopic (n = 27 ears) stapedotomy for otosclerosis. Both groups achieved similar hearing improvement with no significant differences in pre-operative and post-operative bone/air conduction thresholds, ABG, and ABG gain (all p > 0.05). The endoscopic stapedotomy group demonstrated reduced postoperative pain (lower VAS scores, p < 0.001), lower early dysgeusia (3.7% vs. 33.3%, p = 0.005), shorter operative time (47.3 vs. 75.4 min, p < 0.001) and improved patient-reported outcomes (higher GBI score, p = 0.014) when compared to microscopic stapedotomy group. No significant differences were observed in postoperative dizziness or late-term dysgeusia between groups. CONCLUSION: This study found similar hearing improvement with both endoscopic and microscopic stapedotomy for otosclerosis. However, the endoscopic approach showed advantages in reduced postoperative pain, early dysgeusia, and operative time, with improved patient-reported quality of life. These findings suggest endoscopic stapedotomy as a valuable alternative to the conventional microscopic approach.

14.
Clin Rheumatol ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39002071

RESUMO

INTRODUCTION: This study aimed to explore ocular manifestations in ANCA-associated vasculitis (AAV), focusing on granulomatosis with polyangiitis (GPA), eosinophilic granulomatosis with polyangiitis (EGPA), and microscopic polyangiitis (MPA) and to examine the associations with laboratory parameters and other systemic manifestations. METHODS: This retrospective study reviewed data from 533 AAV patients across two major Chinese medical centers from January 2016 to November 2023. Data including diagnosis, cranial manifestations of disease, ocular complications, and laboratory parameters were analyzed. Univariate and multivariable logistic regression analyses assessed associations across disease manifestations. Machine learning models were also utilized to predict the risk of retinal/eye involvement in AAV patients. RESULTS: Among 533 patients (210 GPA, 217 MPA, 99 EGPA, and 7 unclassified AAV), ocular complications were observed in 20.64% of them, with a distribution of 36.67% in GPA, 7.37% in MPA, and 18.18% in EGPA. The most common ocular manifestations included scleritis and retro-orbital mass/dacryocystitis, which were notably prevalent in GPA patients. Retinal involvement was observed in 9.09% of EGPA cases. The machine learning models yielded that eosinophil percentage (EOS%), high-sensitivity C-reactive protein (hsCRP), and CD4 + T cell/CD8 + T cell ratio (T4/T8) can predict retinal involvement. Furthermore, the white blood cell, EOS%, APTT, IgA, hsCRP, PR3-ANCA, and T4/T8 can predict eye involvement. CONCLUSION: Ocular manifestations are a prevalent complication across all forms of AAV. Predictive models developed through machine learning offer promising tools for early intervention and tailored patient care. This necessitates a multidisciplinary approach, integrating rheumatology and ophthalmology expertise for optimal patient outcomes.

15.
Materials (Basel) ; 17(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38998199

RESUMO

Loess is widely distributed in the northwest and other regions, and its unique structural forms such as large pores and strong water sensitivity lead to its collapsibility and collapse, which can easily induce slope instability. Guar gum and basalt fiber are natural green materials. For these reasons, this study investigated the solidification of loess by combining guar gum and basalt fiber and analyzed the impact of the guar gum content, fiber length, and fiber content on the soil shearing strength. Using scanning electron microscopy (SEM), the microstructure of loess was examined, revealing the synergistic solidification mechanism of guar gum and basalt fibers. On this basis, a shear strength model was established through regression analysis with fiber length, guar gum content, and fiber content. The results indicate that adding guar gum and basalt fiber increases soil cohesion, as do fiber length, guar gum content, and fiber content. When the fiber length was 12 mm, the fiber content was 1.00%, and the guar gum content was equal to 0.50%, 0.75%, or 1.00%, the peak strength of the solidified loess increased by 82.80%, 85.90%, and 90.40%, respectively. According to the shear strength model, the predicted and test data of the shear strength of solidified loess are evenly distributed on both sides of parallel lines, indicating a good fit. These findings are theoretically significant and provide practical guidance for loess solidification engineering.

16.
Materials (Basel) ; 17(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38998233

RESUMO

Loess has the characteristics of loose, large pore ratio, and strong water sensitivity. Once it encounters water, its structure is damaged easily and its strength is degraded, causing a degree of subgrade settlement. The water sensitivity of loess can be evaluated by permeability and disintegration tests. This study analyzes the effects of guar gum content, basalt fiber content, and basalt fiber length on the permeability and disintegration characteristics of solidified loess. The microstructure of loess was studied through scanning electron microscopy (SEM) testing, revealing the synergistic solidification mechanism of guar gum and basalt fibers. A permeability model was established through regression analysis with guar gum content, confining pressure, basalt fiber content, and length. The research results indicate that the addition of guar gum reduces the permeability of solidified loess, the addition of fiber improves the overall strength, and the addition of guar gum and basalt fiber improves the disintegration resistance. When the guar gum content is 1.00%, the permeability coefficient and disintegration rate of solidified soil are reduced by 50.50% and 94.10%, respectively. When the guar gum content is 1.00%, the basalt fiber length is 12 mm, and the fiber content is 1.00%, the permeability of the solidified soil decreases by 31.9%, and the disintegration rate is 4.80%. The permeability model has a good fitting effect and is suitable for predicting the permeability of loess reinforced with guar gum and basalt fiber composite. This research is of vital theoretical worth and great scientific significance for guidelines on practicing loess solidification engineering.

17.
Materials (Basel) ; 17(13)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38998288

RESUMO

A low-carbon and environmentally friendly EICP method for repairing concrete cracks is presented to prolong the service life of concrete. In this study, we took concrete as the research object and quartz sand as the filling medium and employed the EICP injection method to repair concrete cracks. The internal repair effect of EICP on concrete cracks was evaluated with a combination of ultrasonic and compressive strength tests. The concrete repair mechanism of EICP was identified with a combination of EDS, XRD, and SEM tests. The results indicate that with an increase in the fracture depth, the ultrasonic sound time of the crack specimen increased gradually, and the ultrasonic wave transit time value of the crack specimen decreased significantly after EICP repair. After repair, the compressive strength rose. The highest compressive-strength recovery rate of a 0.3 mm wide specimen is 98.41%. The calcium carbonate crystal formed using EICP is vaterite. The probability density function model of the Laplace distribution was constructed, which showed good applicability and consistency in the ultrasonic sound time and compressive strength measured via experiments. The formed calcium carbonate crystals can be tightly and evenly attached to the cracks with the EICP injection repair method, resulting in a better repair effect.

18.
Materials (Basel) ; 17(13)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38998307

RESUMO

Geopolymers, as a novel cementitious material, exhibit typical brittle failure characteristics under stress. To mitigate this brittleness, fibers can be incorporated to enhance toughness. This study investigates the effects of varying polypropylene fiber (PPF) content and fiber length on the flowability, mechanical properties, and flexural toughness of coal gangue-based geopolymers. Microstructural changes and porosity variations within the Fiber-Reinforced Geopolymer Mortar(GMPF) matrix were observed using scanning electron microscope (SEM) and Low field NMR(LF-NMR) to elucidate the toughening mechanism of PPF-reinforced geopolymers. The introduction of fibers into the geopolymer matrix demonstrated an initial bridging effect in the viscous geopolymer slurry, with a 3.0 vol% fiber content reducing fluidity by 5.6%. Early mechanical properties of GMPF were enhanced with fiber addition; at 1.5 vol% fiber content and 15 mm length, the 3-day flexural and compressive strengths increased by 30.81% and 17.4%, respectively. Furthermore, polypropylene fibers significantly improved the matrix's flexural toughness, which showed an increasing trend with higher fiber content. At a 3.0 vol% fiber content, the flexural toughness index increased by 198.35%. The data indicated that a fiber length of 12 mm yielded the best toughening effect, with an 84.03% increase in the flexural toughness index. SEM observations revealed a strong interfacial bond between fibers and the matrix, with noticeable damage on the fiber surface due to frictional forces, and fiber pull-out being the predominant failure mode. Porosity testing results indicated that fiber incorporation substantially improved the internal pore structure of the matrix, reducing the median pore diameter of mesopores and converting mesopores to micropores. Additionally, the number of harmless and less harmful pores increased by 23.01%, while the number of more harmful pores decreased by 30.43%.

19.
Plants (Basel) ; 13(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38999593

RESUMO

Bassia indica (Wight) A.J. Scott is an Indian origin plant with documented medicinal and nutritional value, but has not been fully characterized yet. The present study was designed to establish pharmacognostic standards for the proper identification of the B. indica plant and its chemical characterization. The plant was standardized with World Health Organization (WHO) standardization tools and chemically characterized by Fourier transform infrared spectroscopy (FTIR) and gas chromatography-mass spectroscopy (GC-MS) analysis. Antibacterial potential was assessed by the zone of inhibition and minimum inhibitory concentration (MIC), and molecular docking studies were also performed. Pharmacognostic evaluation established the macroscopic and microscopic parameters for the identification of whole plant and its powder. Physicochemical parameters were also set forth while quantitative phytochemical analysis showed that the ethyl acetate fraction had the highest quantity of phenols, flavonoids, and tannins. FTIR analysis showed several functional groups such as phenols, alkanes, and alcohols while 55 phytochemicals were identified in the GC-MS analysis of the crude fraction. The crude extract and other fractions showed marked antibacterial activity, while the ethyl acetate fraction showed the least MIC (1.95-31.25 mg/mL). Phytochemicals identified in the GC-MS showed good molecular docking interactions against the DNA gyrase subunit B of bacteria with binding energies ranging from -4.2 to -9.4 kcal/mol. The current study describes the pharmacognostic characterization and phytochemical profiling of B. indica and provides scientific evidence to support its use in infections.

20.
Nutrients ; 16(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38999829

RESUMO

Microscopic colitis (MC) and coeliac disease (CD) are common associated gastrointestinal conditions. We present the largest study assessing hospitalisation in patients with MC and the effect of a concomitant diagnosis of CD. Data were retrospectively collected between January 2007 and December 2021 from all patients diagnosed with MC and compared to a database of patients with only CD. In total, 892 patients with MC (65% female, median age 65 years (IQR: 54-74 years) were identified, with 6.4% admitted to hospital due to a flare of MC. Patients admitted were older (76 vs. 65 years, p < 0.001) and presented with diarrhoea (87.7%), abdominal pain (26.3%), and acute kidney injury (17.5%). Treatment was given in 75.9% of patients, including intravenous fluids (39.5%), steroids (20.9%), and loperamide (16.3%). Concomitant CD was diagnosed in 3.3% of patients and diagnosed before MC (57 versus 64 years, p < 0.001). Patients with both conditions were diagnosed with CD later than patients with only CD (57 years versus 44 years, p < 0.001). In conclusion, older patients are at a higher risk of hospitalisation due to MC, and this is seen in patients with a concomitant diagnosis of CD too. Patients with MC are diagnosed with CD later than those without.


Assuntos
Doença Celíaca , Colite Microscópica , Hospitalização , Humanos , Doença Celíaca/diagnóstico , Doença Celíaca/complicações , Doença Celíaca/epidemiologia , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Hospitalização/estatística & dados numéricos , Colite Microscópica/epidemiologia , Colite Microscópica/diagnóstico , Prognóstico , Fatores de Risco , Diarreia/etiologia , Adulto , Fatores Etários
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